Merbel
Merbel is a frozen moon orbiting Glumo. Looking at the trailer for KSP 2, we can assume that Merbel has a high inclination orbit, however, this could change when released.
Appearance
Merbel shares a lot of similarities with Laythe they are both moons of a gas gaint liquid seas (possibly also water) and a blue atmosphere (possibly also oxygen rich but in the cinematic trailer they did not take their helmets off, as well as encased habitat domes, however the cinematic trailer was made quite early in development and at that time it may not had been decided if merbels atmosphere would be breathable.)
Merbel's landforms are mostly covered with ice and rock. However, Merbel also has seas. Its still unknown what the sea's are made of, but there's a possibility that there made up of liquid oily ethane and methane much like Titan.
Also like Titan, Merbel has an atmosphere, however it is unknown what its made up of.
It will be added in either the upcoming Interstellar Update or Exploration Update in KSP 2.